Check your HTTP Header
A tool to check your HTTP header is very useful, indeed. For example, once a 301 redirect is done, check it to make sure it works. If you check the header for http://smartlabsoftware.com you will see that it returns in the receiving header, a status of 301 and the new location will be http://www.smartlabsoftware.com
Checking http://www.smartlabsoftware.com/invalid.htm will produce a 404 return code (file not found).
Other bits of information, such as what server (e.g. Apache) and its version (e.g. 1.3.33) are useful to know.
Doug